The broad objective of this laboratory research project is to obtain as much information as possible about the ovarian enzyme complex which catalyzes the aromatase reaction, the final step in the biosynthesis of the steroid hormone estrogens. We will determine the most favored substrates for the enzyme, its necessary cofactors and inhibitors. We will examine the kinetic and chemical mechanisms of the reaction. We will identify any essential prosthetic groups such as cytochrome P-450. We will study the protein subunit structure of the enzyme. We will examine the regulation of the enzyme's activity and biosynthesis. We will attempt to relate all these functions and properties of the enzyme to the biosynthesis of steroid hormones in the ovary. This fundamental research may be of great value in increasing our understanding of important events in reproductive biology.